2022年生产管理系统外文翻译 .pdf

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1、1 本科毕业设计 ( 论文 ) 外文翻译译文：生产管理系统朗文出版社，第七版（ 1999年 10 月） ，页码 :938，C.J. 信息是管理上的一项极为重要的资源，管理工作的成败取决于能否做出有效的决策，而决策的正确程度则在很大程度上取决于信息得质量。所以能否有效的管理信息成为企业的首要问题，管理信息系统MIS 在强调管理、强调信息的现代社会中越来越得到普及。企业信息管理通常是比较复杂，由于各类信息繁多难归集，利用计算机支持企业高效率完成企业信息管理，是适应现代企业制度要求，推动企业信息管理走向科学化、社会化、规范化和自动化，从而提高企业信息管理效率。数据库（ database ）又称为电子

2、数据库，是专门组织起来的一组数据或信息，其目的是为了便于计算机快速查询及检索。数据库的结构是专门设计的，在各种数据处理操作命令的支持下，可以简化数据的存储，检索，修改和删除。数据库可以存储在磁盘，磁带，光盘或其他辅助存储设备上。数据库由一个或一套文件组成，其中的信息可以分解为记录，每一记录又包含一个或多个字段（或称为域） 。字段是数据存取的基本单位。数据库用于描述实体，其中的一个字段通常表示与实体的某一属性相关的信息。通过关键字以及各种分类（排序）命令，用户可以对多条记录的字段进行查询，重新整理， 分组或选择， 以实体对某一类数据的检索，也可以生成报表。所有数据库（最简单的除外）中都有复杂的数

3、据关系及其链接。处理与创建，访问以及维护数据库记录有关的复杂任务的系统软件包叫做数据库管理系统（DBMS ） 。DBMS软件包中的程序在数据库与其用户间建立接口。（这些用户可以是应用程序员，管理员及其他需要信息的人员和各种操作系统程序）。DBMS 可组织，处理和表示从数据库中选出的数据元。该功能使决策者能搜索，探查和查询数据库的内容，从而对在正规报告中没有的，不再出现的且无法预料的问题做出回答。这些问题最初可能是模糊的并且（或者）是定义不恰当的，但是人们可以浏览数据库直到获得所需的信息。简言之，DBMS 将“管理”存储的数据项，并从公共数据库中汇集所需的数据项以回答非程序员的询问。DBMS 由

4、 3 个主要部分组成： （ 1）存储子系统，用来存储和检索文件中的数据；（2）建模和操作子系统，提供组织数据以及添加，删除，维护，更新数据的方法；（3）用户和DBMS之间的接口。在提高数据库管理系统的价值和有效性方面正在展现以下一些重要发展趋势；1. 管理人员需要最新的信息以做出有效的决策。2. 客户需要越来越复杂的信息服务以及更多的有关其订单，发票和账号的当前信息。名师资料总结 - - -精品资料欢迎下载 - - - - - - - - - - - - - - - - - - 名师精心整理 - - - - - - - 第 1 页，共 5 页 - - - - - - - - - 2 3. 用户

5、发现他们可以使用传统的程序设计语言，在很短的一段时间内用数据库系统开发客户应用程序。4. 商业公司发现了信息的战略价值，他们利用数据库系统领先于竞争对手。数据库模型描述了在数据库中结构化和操纵数据的方法，模型的结构部分规定了数据如何被描述（例如树，表等）：模型的操纵部分规定了数据添加，删除，显示，维护，打印，查找，选择，排序和更新等操作。类似的，分布式数据库指的是数据库的各个部分分别存储在物理上相互分开的计算机上。分布式数据库的一个目的是访问数据信息时不必考虑其他位置。注意，一旦用户和数据分开，通信和网络则开始扮演重要角色。分布式数据库需要部分常驻于大型主机上的软件，这些软件在大型机和个人计算

6、机之间建立桥梁，并解决数据格式不兼容的问题。在理想情况下，大型主机上的数据库看起来像是一个大的信息仓库，而大部分处理则在个人计算机上完成。分布式数据库系统的一个缺点是它们常以主机中心模型为基础，在这种模型中，大型主机看起来好像是雇主，而终端和个人计算机看起来好像是奴隶。但是这种方法也有许多优点：由于数据库的集中控制，前面提到的数据完整性和安全性的问题就迎刃而解了。当今的个人计算机，部门级计算机和分布式处理都需要计算机之间以及应用程序之间在相等或对等的基础上相互通信，在数据库中客户机/ 服务器模型为分布式数据库提供了框架结构。利用相互连接的计算机上运行的数据库应用程序的一种方法是将程序分解为相互

7、独立的部分。客户端是一个最终用户或通过网络申请资源的计算机程序，服务器是一个运行着的计算机软件，存储着那些通过网络传输的申请。当申请的资源是数据库中的数据时，客户机/ 服务器模型则为分布式数据库提供了框架结构。文件服务器指的是一个通过网络提供文件访问的软件，专门的文件服务器是一台被指定为文件服务器的计算机。这是非常有用的，例如，如果文件比较大而且需要快速访问，在这种情况下，一台微型计算机或大型主机将被用作文件服务器。分布式文件服务器将文件分散到不同的计算机上，而不是将它们集中存放到专门的文件服务器上。后一种文件服务器的优点包括在其他计算机上存储和检索文件的能力，并可以在每一台计算机上消除重复文

8、件。然而，一个重要的缺点是每个读写请求需要在网络上传播，在刷新文件时可能出现问题。假设一个用户申请文件中的一个数据并修改它，同时另外一个用户也申请这个数据并修改它， 解决这种问题的方法叫做数据锁定，即第一个申请使其他申请处于等待状态，直到完成第一个申请，其他用户可以读取这个数据，但不能修改。数据库服务器是一个通过网络为数据库申请提供服务的软件，例如，假设某个用户在他的个人计算机上输入了一个数据查询命令，如果应用程序按照客户机/ 服务器模型设计，那么个人计算机上的查询语言通过网络传送数据库服务器上，当发现数据时发出通知。在工程界也有许多分布式数据库的例子，如SUN公司的网络文件系统（NFS ）被

9、应用到计名师资料总结 - - -精品资料欢迎下载 - - - - - - - - - - - - - - - - - - 名师精心整理 - - - - - - - 第 2 页，共 5 页 - - - - - - - - - 3 算机辅助工程应用程序中，将数据分散到由SUN工作站组成的网络上的不同硬盘之间。分布式数据库是革命性的进步，因为把数据存放在被使用位置上是很合乎常理的。例如一个大公司不同部门之间的计算机，应该将数据存储在本地，然而，当被授权的管理人员需要整理部门数据时，数据应该能够被访问。数据库信息系统软件将保护数据库的安全性和完整性，对用户而言，分布式数据库和非分布式数据库看起来没有什

10、么差别。原文：Production Management System Addison Wesley Longman; 7th edition (October 1999) ，Pages 517-538 ，C. J. Date The information is an extremely important resources of the management，the success or failure that manages the work is decided by and can do a valid decision,but the right degree of the d

11、ecision then to a large extent be decided by the information get quantity. So can effectively of management information become initial problem of the business enterprise, the management information system MIS get the universality more and more in emphasize manage, emphasize modern society of informa

12、tion. The business enterprise information the management is usually more complicated, because each kind of information is numerous difficult return to gather, make use of the calculator support business enterprise high-efficiency complete the business enterprise information management, is to adapt t

13、he modern business enterprise system request, push the business enterprise information management alignment scientific, acculturate, the norm turns and automates, thus raising the business enterprise information management efficiency. A database (sometimes spelled data base) is also called an electr

14、onic database , referring to any collection of data, or information, that is specially organized for rapid search and retrieval by a computer. Databases are structured to facilitate the storage, retrieval, modification, and deletion of data in conjunction with various data-processing operations .Dat

15、abases can be stored on magnetic disk or tape, optical disk, or some other secondary storage device. A database consists of a file or a set of files. The information in these files may be broken down into records, each of which consists of one or more fields. Fields are the basic units of data stora

16、ge , and each field typically contains information pertaining to one aspect or attribute of the entity described by the database . Using keywords and various sorting commands, users can rapidly search , rearrange, group, and select the fields in many records to retrieve or create reports on particul

17、ar aggregate of data. Complex data relationships and linkages may be found in all but the simplest databases .The system software package that handles the difficult tasks associated with creating ,accessing, and maintaining database records is called a database management system(DBMS).The programs i

18、n a DBMS package establish an interface between the database itself and the users of the database. (These users may be applications programmers, managers and others with information needs, and various OS programs.) A DBMS can organize, process, and present selected data elements from the database. T

19、his capability enables decision makers to search, probe, and query database contents in order to extract answers to nonrecurring and unplanned questions that aren t available in regular reports. These 名师资料总结 - - -精品资料欢迎下载 - - - - - - - - - - - - - - - - - - 名师精心整理 - - - - - - - 第 3 页，共 5 页 - - - - -

20、 - - - - 4 questions might initially be vague and/or poorly defined ,but people can “ browse”through the database until they have the needed information. In short, the DBMS will “ manage” the stored data items and assemble the needed items from the common database in response to the queries of those

21、 who aren t programmers. A database management system (DBMS) is composed of three major parts:(1)a storage subsystem that stores and retrieves data in files;(2) a modeling and manipulation subsystem that provides the means with which to organize the data and to add , delete, maintain, and update the

22、 data;(3)and an interface between the DBMS and its users. Several major trends are emerging that enhance the value and usefulness of database management systems; Managers: who require more up-to-data information to make effective decision Customers: who demand increasingly sophisticated information

23、services and more current information about the status of their orders, invoices, and accounts. Users: who find that they can develop custom applications with database systems in a fraction of the time it takes to use traditional programming languages. Organizations : that discover information has a

24、 strategic value; they utilize their database systems to gain an edge over their competitors. A data model describes a way to structure and manipulate the data in a database. The structural part of the model specifies how data should be represented(such as tree, tables, and so on ).The manipulative

25、part of the model specifies the operation with which to add, delete, display, maintain, print, search, select, sort and update the data. Similarly , a distributed database is one in which different parts of the database reside on physically separated computers . One goal of distributed databases is

26、the access of information without regard to where the data might be stored. Keeping in mind that once the users and their data are separated , the communication and networking concepts come into play . Distributed databases require software that resides partially in the larger computer. This softwar

27、e bridges the gap between personal and large computers and resolves the problems of incompatible data formats. Ideally, it would make the mainframe databases appear to be large libraries of information, with most of the processing accomplished on the personal computer. A drawback to some distributed

28、 systems is that they are often based on what is called a mainframe-entire model , in which the larger host computer is seen as the master and the terminal or personal computer is seen as a slave. There are some advantages to this approach . With databases under centralized control , many of the pro

29、blems of data integrity that we mentioned earlier are solved . But today s personal computers, departmental computers, and distributed processing require computers and their applications to communicate with each other on a more equal or peer-to-peer basis. In a database, the client/server model prov

30、ides the framework for distributing databases. One way to take advantage of many connected computers running database applications is to distribute the application into cooperating parts that are independent of one another. A client is an end user or computer program that requests resources across a

31、 network. A server is a computer running software that fulfills those requests across a network . When the resources are data in a database ,the client/server model provides the framework for distributing database. A file serve is software that provides access to files across a network. A dedicated

32、file server is a single computer dedicated to being a file server. This is useful ,for example ,if the files are large and require fast access .In such cases, a minicomputer or mainframe would be used as a file server. A 名师资料总结 - - -精品资料欢迎下载 - - - - - - - - - - - - - - - - - - 名师精心整理 - - - - - - - 第

33、 4 页，共 5 页 - - - - - - - - - 5 distributed file server spreads the files around on individual computers instead of placing them on one dedicated computer. Advantages of the latter server include the ability to store and retrieve files on other computers and the elimination of duplicate files on each

34、 computer. A major disadvantage , however, is that individual read/write requests are being moved across the network and problems can arise when updating files. Suppose a user requests a record from a file and changes it while another user requests the same record and changes it too. The solution to

35、 this problems called record locking, which means that the first request makes others requests wait until the first request is satisfied . Other users may be able to read the record, but they will not be able to change it . A database server is software that services requests to a database across a

36、network. For example, suppose a user types in a query for data on his or her personal computer . If the application is designed with the client/server model in mind ,the query language part on the personal computer simple sends the query across the network to the database server and requests to be n

37、otified when the data are found. Examples of distributed database systems can be found in the engineering world. Sun s Network Filing System(NFS),for example, is used in computer-aided engineering applications to distribute data among the hard disks in a network of Sun workstation. Distributing data

38、bases is an evolutionary step because it is logical that data should exist at the location where they are being used . Departmental computers within a large corporation ,for example, should have data reside locally , yet those data should be accessible by authorized corporate management when they wa

39、nt to consolidate departmental data . DBMS software will protect the security and integrity of the database , and the distributed database will appear to its users as no different from the non-distributed database . Examples of distributed database systems can be found in the engineering world. Sun

40、s Network Filing System(NFS),for example, is used in computer-aided engineering applications to distribute data among the hard disks in a network of Sun workstation. Distributing databases is an evolutionary step because it is logical that data should exist at the location where they are being used

41、. Departmental computers within a large corporation ,for example, should have data reside locally , yet those data should be accessible by authorized corporate management when they want to consolidate departmental data . DBMS software will protect the security and integrity of the database , and the distributed database will appear to its users as no different from the non-distributed database . 名师资料总结 - - -精品资料欢迎下载 - - - - - - - - - - - - - - - - - - 名师精心整理 - - - - - - - 第 5 页，共 5 页 - - - - - - - - -